/**
给你一棵二叉树的根节点 root ，翻转这棵二叉树，并返回其根节点。
输入：root = [4,2,7,1,3,6,9]
输出：[4,7,2,9,6,3,1]
输入：root = [2,1,3]
输出：[2,3,1]
 */
import arrayToTree from './0-数组转为二叉树.js'
import levelOrder from './0-层序遍历.js'
function invertTree(root) {
  if(!root) return null
  const left = invertTree(root.left)
  const right = invertTree(root.right)
  root.left = right
  root.right = left
  return root
}
const root = [4,2,7,1,3,6,9]
const res = invertTree(arrayToTree(root))
console.log(levelOrder(res))